if(strlen($client->client_id) == 0|| strlen($client->client_secret) == 0)
die('Please go to Tumblr Apps page http://www.tumblr.com/oauth/apps , '.'create an application, and in the line '.$application_line.' set the client_id to Consumer key and client_secret with Consumer secret. '.'The Default callback URL must be '.$client->redirect_uri);